Device for joining together parts of a piece of furniture

ABSTRACT

A device for securing together individual parts, such as wooden panels, of a piece of furniture is formed of an elongated Ushaped member which forms a groove within which a pair of strips are provided extending along the oppositely disposed legs or flanges of the U-shaped member. T-shaped recesses are formed in the edges of the strips located along the opening to the groove in the U-shaped member and connecting members are arranged to be interlocked into these recesses. One panel of the piece of furniture can be held between the strips within the groove in the U-shaped member while additional parts or panels are attached to the members interlocked into the recesses in the strips.

United States Patent Hills [451 May 30, 1972 [54] DEVICE FOR JOININGTOGETHER PARTS OF A PIECE OF FURNITURE [72] Inventor: Karl Huls,Schoppenkamp 29, 4424 Stadtlohn, Germany [22] Filed: July 16, 1970 [211App]. No.: 55,533

[30] Foreign Application Priority Data Sept. 25, 1969 Germany ..P 19 48400.5

[52] US. Cl. ..287/20.92 C, 21 1/177, 287/2092, 287/2092 D, 108/108 [51]Int. Cl ..Fl6b 5/07 [58] Field of Search ..287/189.36 R, 189.36 C, 20.92C, 287/2092 D, 20.92, 189.36 D; 52/730, 732;

[56] References Cited UNITED STATES PATENTS 1,930,856 10/1933 Mioton..287/189.36 R

Rosenberg Primary Examiner-David .1. Williamowsky AssistantExaminer-Wayne L. Shedd Attorney-MCGlew and Toren [57] ABSTRACT A devicefor securing together individual parts, such as wooden panels, of apiece of furniture is formed of an elongated U-shaped member which fonnsa groove within which a pair of strips are provided extending along theoppositely disposed legs or flanges of the U-shaped member. T-shapedrecesses are formed in the edges of the strips located along the openingto the groove in the U-shaped member and connecting members are arrangedto be interlocked into these recesses. One panel of the piece offurniture can be held between the strips within the groove in theU-shaped member while additional parts or panels are attached to themembers interlocked into the recesses in the strips.

16 Claims, 4 Drawing Figures PATENTEDMAYSO I972 3,666 303 SHEET 1 OF 2 Ar mews s DEVICE FOR JOINING TOGETHER PARTS OF A PIECE OF FURNITURESUMMARY OF THE INVENTION The present invention is directed to a devicefor joining together different parts or panels of a piece of woodenfumiture and, more particularly, it is concerned with a device whichincludes a U-shaped member and other members which can be secured withinrecesses formed in the U-shaped member for securing together differentparts of the piece of furniture.

In the past, U-shaped members have been used for securing separate partsof a piece of furniture together. Projections have been formed withinthe interior of the U-shaped member and other members are provided whichinterengage with the projections. One part of the piece of furniture issecured within the groove formed by the U-shaped member and other partsare attached to the members which are secured to the U- shaped member.In a piece of furniture, such as a cabinet the various parts, such aspanels and doors, can be assembled together to provide the requiredstrength and at the same time afford the requisite stability for torsionresistance.

It is the primary object of the present invention to provide an improvedarrangement of such a device using a U-shaped member in which theinterengaging or interlocking parts are simplified and aflord increasedstrength and stability.

Therefore, in accordance with the present invention, an elongatedU-shaped member is provided having a pair of spaced legs or flangesextending along and from the opposite longitudinally extending edges ofa web. The U-shaped member forms a groove within which a pair of flatstrips are arranged, one extending along each of the inside surfaces ofthe legs and the outer edges of these strips extending along the openinginto the groove in the U-shaped member are provided with shaped recessesfor receiving similarly shaped projections on connecting members forsecuring the connecting members in interlocking engagement.

Another characteristic of the invention is the provision of stops alongthe edges of the legs of the U-shaped member at the opening into itsgroove so that the strips can be held between these stops and the innersurface of the web. The thickness of the strips can be equal to thecorresponding dimension of the stops or the strips can have a thickerdimension than the corresponding dimension of the stops so that theyextend inwardly into the groove beyond the stops for effecting theinterlocking engagement with the other members for securing the parts ofthe piece of furniture together.

Since the U-shaped member and the strips are separate, it is easier toform the recesses which provide the interlocking engagement. TheU-shaped member can be formed in one part, for example of aluminum, andthe flat strips can be formed in another part of a similar metal, andthen the strips can be punched or reworked to form the required recessconfigurations. The production of the U-shaped members and the flatstrips of metal is advisable because it insures the necessary strengthof the device. However, as this technology develops it is quite possiblethat plastics will be found which have the necessary stability andstrength for use in place of the metal strips.

in two German utility models, Nos. 1,977,136 and 1,996,198, U-shapedmembers have been disclosed which are provided with an insert forreceiving one of the parts of the piece of furniture which is to bejoined to another part. However, in these arrangements the insert is aU-shaped part formed, for example of plastic, and it is configured onits exterior surface so that it cooperates with a corresponding profileon the inner wall of the Ushaped member into which it is inserted toinsure the mounting support of the U-shaped insert. A U shaped insertlocated within a U-shaped member has the disadvantage that, because ofthe web portion of the U- shaped insert, the part of the piece offurniture can not be inserted a sufficient distance into the combinedU-shaped structure to afford adequate mounting support withoutincreasing the size of the U-shaped member which receives the insert.However, the increase in the size of the U-shaped member results inunnecessary costs and, of course, increases the size of the jointbetween the various parts of the piece of furniture. Accordingly, theseknown constructions are not comparable to the arrangement disclosed inthe present invention.

Furthermore, another feature of the present invention is the provisionof aligned bores through the U-shaped member and the flat strips throughwhich threaded members, such as screws, can be inserted into a crossconnector provided through an aligned hole in the part to be securedwithin the groove in the U-shaped member. Preferably, the crossconnector is polygonal so that when inserted in the part or panel itwill be held against turning. Further, the length of the cross connectorcorresponds to the thickness of the part secured in the groove andthreaded bores are provided within the cross connector for receiving thethreaded members which extend through the bores in the U-shaped memberand the strips. With this arrangement it is possible to avoid the use ofhooks which have been necessary in the past for securing the part withinthe groove in the U-shaped member. Furthennore, with this arrangement itis possible to avoid bulging of the U- shaped member even when it is ofa considerable height, since the legs of the U-shaped member are rigidlyconnected with one another through the threaded members and the crossconnector provided through the part secured within the groove in theU-shaped member.

Use of the cross connector has the additional advantage, when a hingemember has projections which interengage with the recesses in the stripswithin the U-shaped member, that additional locking is achieved by meansof a screw which is engaged within the threaded bore in the crossconnector.

Another characteristic of the invention is the provision of flangesalong one or both of the exterior surfaces of the legs on the U-shapedmember. The flanges are arranged normally to the surfaces of the legsand serve as stop edges for the parts of the piece of furniture whichare secured to the U-shaped member. The spacing of the flanges from theedges of the legs can be arranged to correspond to the thickness of thepart being mounted on the U-shaped member so that the part will have oneof its surfaces flush with the plane of the opening to the groove in theU-shaped member or the plane of the exterior surface of its web.

Various forms of members can be provided for interlocking engagementwith the U-shaped member to accomodate the interconnection of thedifferent parts of a piece of furniture. One such member is an abutmentplate with projections extending at right angles to its plate surfaceand which interengage in the recesses fonned in the strips positioned inthe U-shaped member. An opening can be arranged in the abutment platefor an elastically deformable pushbutton which contacts one surface ofthe part held by the abutment plate in a manner so that the member isheld between the flange on the U-shaped member and the opposite surfaceof the abutment plate. Where a door hinge is engaged in the U-shapedmember a slot-like recess is formed in the hinge for adapting to theposition of the flange.

The stops located at the opening to the groove in the U- shaped membercan be chamfered to facilitate the insertion of the part of the piece offurniture into the groove and to give the U-shaped member a certainesthetic appearance. In the construction of a cabinet wall, shelf orother piece of furniture using the U-shaped member of the presentinvention, a bottom frame support can be provided with projections forengagement into the recesses in the U-shaped member with a right angledpart extending from the support. In order to provide a stronger bottomframe support, which is of particular importance in so-calledconstruction bottoms, it is preferable to provide the right angled partwith an opening through which a connector member can be inserted forsecuring the frame bottom to the support.

The various features of novelty which characterize the invention arepointed out with particularity in the claims anthere is illustrated anddescribed a preferred embodiment of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 is an exploded perspective view of a device, in accordance withthe present invention, for securing together different parts of a pieceof furniture;

FIG. 2 is a top view of the device shown in FIG. 1 arranged to secure acabinet door to the side wall of a cabinet;

FIG. 3 is a view, partly in section, of the device shown in FIG. 1 forsecuring rear cabinet walls to the side wall of a cabinet;

FIG. 4 is a side view part, partly in section, showing the attachment ofa bottom frame support into the device shown in FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION In FIGS. 2,3, and 4 various partsof a piece of furniture are shown in an interconnected arrangement. Thepiece of furniture is a cabinet comprised of a side wall 1, rear walls3, a cabinet door 4, and a U-shaped member 5 which cooperates inassembling the various parts together. The U-shaped member has a pair oflongitudinally extending legs 6 and 7 which extend perpendicularly fromthe opposite longitudinally extending edges of a web 8. The legs 6 and 7and the web 8 combine to form a groove into which the side wall 1 of thecabinet is shown secured. At the opening to the groove formed in the U-shaped member 5 a pair of stops 30 and 31 extend inwardly from the freeends of the legs 6 and 7, respectively, and the surfaces of the stopsare chamfered as shown at 32, note FIG. 1.

Within the groove formed by the U-shaped member 5 a pair of flat strips33 and 34 are arranged, each extending along one of the interior facesof the legs 6 and 7. The strips, 33 and 34, extend between the interiorsurface of the web 8 and the interior surface of the stops 30 and 31 ascan be seen in FIG. 4. Spaced along the edges of the strips contactingthe stops and located at the opening to the groove in the U-shapedmember 5 are T-shaped recesses which are arranged so that the opening tothe recess along the length of the strip is less than the length of therecess spaced inwardly from its opening. Due to this T-shapedconfiguration of the recess a pair of oppositely directed projections orteeth, 11,12 are provided at the opening to the recess. FIGS. 2 and 3clearly indicate that the strips 33, 34 are thicker than thecorresponding dimension of the stops 30, 31, however, it is alsopossible to reduce the thickness of the strips or to have the stops 30,31 project further across the opening into the groove in the U-shapedmember.

Adjacent the free ends of the legs 6 and 7 of the U-shaped member 5,aligned bores 35 and 36 are provided which coincide with similar bores37, 38 provided in the flat strips 33 and 34. Though not shown in thedrawing, a hole is provided in the side wall 1 which coincides with thebores 35 to 38. To effect the securement of the side wall within theU-shaped member, a cross connector 39 is positioned in the bore throughthe side wall and the connector has a hexagonal transverse cross sectionwhose outer circumference is somewhat larger than the bore through theside wall so that the connector is tightly secured within the wall andis held against turning. The length 1" of the cross connector 33, noteFIG. 1, corresponds substantially to the thickness of the side wallsecured within the U-shaped member. At its opposite ends the crossconnector 39 is provided with bores 40, 41 each having a female threadfor receiving the screws 42, 43 which extend through the opposite legs 6and 7 of the U-shaped member and through the strips 33, 34. With thisarrangement of the screws 42, 43 and the cross connector it is possibleto tighten the legs 6 and 7 of the U-shaped member towards one anotherand to secure the side wall in position within the groove in theU-shaped member.

In FIG. 1, on the outer surfaces of the legs 6 and 7 of the U- shapedmember 5, flanges 44, 45 are provided which extend perpendicularlyoutwardly from the legs. It can be appreciated that the U-shaped membercan be provided without any flanges extending from its legs or, asrepresented in FIG. 2, a flange 45 can be provided extending from onlyone leg of the member. As can be noted in FIGS. 2 and 3, the flanges arelocated intermediate the ends of the legs so that they provide a supportfor one surface of one of the cabinet walls and the dimension betweenthe support surface of the flange and the adjacent end of the leg isequal approximately to the thickness of the wall positioned between theflange and the end of the leg, note the rear wall 3 in FIG. 3. In FIG. 2the thickness dimension of the cabinet door 4 is approximately equal tothe distance between the flange 45 and the outer surface of the web 8 ofthe U-shaped member 5.

In FIG. 3 the rear walls 3 are secured to the U-shaped member 5 and theside wall I by means of a pair of correspondingly arranged abutmentplates 46 and 47. In FIG. 1, the abutment plate 46 is illustrated on anenlarged scale and is provided with a plate surface extendingperpendicularly to the legs and strips of the U-shaped member with apair of spaced projections 48 arranged to extend inwardly toward and tofit within the recesses in the strips 33, 34. As can be noted, theprojections 48 have a T-shaped configuration similar to that of therecesses in the strips 33, 34 to provide the requisite interlockingengagement between the abutment plate 46 and the U-shaped member 5. Inthe surface of the abutment plate extending transversely from theU-shaped member an opening 46 is arranged which holds a pushbutton 50,note FIG. 3, which is formed of an elastic material, for example rubber,and has a side 51 which presses against one surface of the rear wall 3while the other surface along its edge contacts the flanges 44 or 45. Asmentioned above, the distance between the flange 45 and the outersurface of the web 8 of the U- shaped member is selected so that itequals the thickness of the door 4 and the flange 45 serves as a stopfor the door, note FIG. 2.

In FIG. 2 the hinge side of the door is shown and in dashed lines theposition of the door 4 is shown displaced from the opening to thecabinet. As indicated in FIG. 2, a hinge 52 is secured to the door andis interengaged within the U-shaped member 5, and in FIG. 1 the hinge isshown in more detail on an enlarged scale. Extending upwardly anddownwardly from the hinge 52 are projections 53 which are T-shaped attheir ends for engagement within the recesses in the strips so that aninterlocking engagement is provided with the projections II or 12 on thestrips. In addition, to the engagement provided between the projections53 and the recesses in the strips, a screw 54 is provided through thehinge which extends into the aligned bores through one side of theU-shaped member and into the cross connector 39 located within the sidewall 1. Due to the arrangement of the screw 54 and the interengagementwith the strip a firm attachment of the hinge 52 to the U- shaped memberis provided.

In adapting the hinge 52 to the thickness of the side 6 or 7 and theflat strips 33 or 34, a slot 55 is provided with a projecting nose 56which extends along the outer surface of the leg of the U-shaped member.It is not considered that any further explanation of the hinge and itsfunction is required, since these are conventional technical means whichare well known.

In FIG. 4 a bottom frame support 57 is shown in interengagement with theU-shaped member and this support is shown on an enlarged scale inFIG. 1. A projection 58 is provided on each end of the bottom framesupport 57 and the projection is configured so that it engages withinthe recess formed in the strip and is held against one of theprojections 11 or 12 at the opening to the recess. The height of thesupport is such that it fits closely within the opening to the recess,

note FIG. 4. This is characteristic also of the projections 48 on theabutment plate 46 and projections 53 on the hinge 52 which fit closelywithin the recesses in the strip. The bottom frame support 57 extendsforwardly from the opening to the U-shaped member and a projectingsurface extends laterally from one side at a position spacedintermediate the projections 58 which acts as a support for the lowersurface of the bottom frame 62. An opening 60 is provided in theprojecting surface 59 for receiving a screw 61 and a known expansiondowel 63 is provided in the bottom frame 62 so that the screw can belocked into the bottom frame. This attachment arrangement secures thebottom frame against any upward pressure once the screw is inserted.This arrangement is particularly important in the case of so-calledconstruction bottoms.

The embodiments shown in the drawing are provided merely forillustration of the invention and are not intended to limit theapplication of the invention. it will be readily appreciated that theU-shaped member 5 can be used in various ways for securing parts of apiece of furniture together.

What is claimed is:

1. In a device for assembling wooden furniture panels to form a piece offurniture, and of the type including elongated U-shaped members arrangedto conforrningly seat edges of panels and having interlock formationsinterengageable with mating interlock formations on connecting memberssecurable to other panels, the improvement comprising, in combination,an elongated U-shaped member of substantially rectangular crosssectionincluding a web and a pair of legs extending perpendicularly from saidweb to define a groove; a pair of substantially similar elongatedsubstantially rectangular strips each positioned against the innersurface of a respective leg and having an inner edge seating on saidweb, the outer edges of said strips being formed with said interlockformations; a first wooden furniture panel seated in said groove; thethickness of said strips relative to the interior width of said U-shaped member being such that the lateral spacing between said strips issubstantially equal to the thickness of said first wooden furniturepanel, so that said first panel is tightly engaged between said strips;means restraining displacement of said strips outwardly of said groove;at least one metal connecting member having interlock formationsmatingly engaged in interlock formations of one of said strips, eachconnecting member extending outwardly from said groove; and a woodenfurniture panel secured to each connecting member.

2. A device, as set forth in claim 1, wherein said strip formations havea T-shaped configuration in the plane extending along the surface ofsaid leg of said U-shaped member.

3. A device, as set forth in claim 2, wherein the interlock formationson said connecting means have a T-shaped configuration similar to theT-shaped configuration of the interlock formations of said strips.

4. A device, as set forth in claim 1, wherein stops extend along each ofthe outer edges of said legs substantially perpendicularly to the legsand partly across the opening to the groove in said U-shaped member,said stops being arranged in engagement with the outer edges of saidstrips.

5. A device, as set forth in claim 1, wherein said legs of said U-shapedmember and said strips have aligned bores therethrough, a crossconnector arranged to be fitted into a bore in the panel to be securedwithin said groove of said U- shaped member and to be aligned with thebores in said legs and strips, and securing means arranged to extendthrough the bores in said legs and strips into said cross connector forsecuring the panel within said groove and for securing said legs andstrips together.

6. A device, as set forth in claim 5, wherein said cross connector has apolygonally shaped transverse cross section for preventing turning whenit is positioned within a panel, said cross connector having a boretherethrough aligned with the bores in said legs and strips, said crossconnector having a length substantially equal to the thickness of thepanel positioned within said groove, and said securing means comprisingthreaded members each arranged to pass throu the bores in one said legand strip and to be secured within e bore in said cross connector forsecuring the U-shaped member and the panel positioned within its groovetogether.

7. A device, as set forth in claim 1, wherein a flange extends along andoutwardly from the outer surface of at least one of said legs, saidflange being positioned intermediate said web and the outer edge of saidleg.

8. A device, as set forth in claim 7, wherein the distance of saidflange from the outer edge of said leg corresponds substantially to thethickness of a panel to be secured against said flange on the sidethereof facing toward the outer edge of said leg.

9. A device, as set forth in claim 7, wherein the distance of saidflange from the outer wall of said web of said U-shaped membercorresponds substantially to the wall thickness of a panel to bepositioned between the flange and the outer surface of said web.

10. A device, as set forth in claim 7, including a connecting member inthe form of an abutment plate arranged to be interlocked with one ofsaid strips; said abutment plate comprising a plate part and a pair ofT-shaped projections extending perpendicularly from said plate part andconstituting said interlock formations, said T-shaped projections havingmating engagement in T-shaped recesses in the associated strip.

11. A device, as set forth in claim 10, wherein said plate part of saidabutment plate has an opening therethrough, an elastically deformablebutton-like member positioned within said opening and arranged to extendfrom one surface of said plate part into engagement with the panel to besecured thereby and providing contacting engagement with the panel onone side while the opposite side of the panel is secured against saidflange extending outwardly from said leg on said U-shaped member.

12. A device, as set forth in claim 4, wherein the surfaces of saidstops adjacent the opening into said groove in said U- shaped member arechamfered.

13. A device, as set forth in claim 4, wherein said strips have athickness which corresponds to the dimension of said stops extendingfrom the inner surface of said legs of said U-shaped I member.

14. A device, as set forth in claim 4, wherein said strips have athickness which is greater than the dimension of said stops extendingfrom the inner surface of said legs of said U-shaped member so that thestrips extend further into said groove in said U-shaped member than dosaid stops.

15. A device, as set forth in claim 1, including a connecting member inthe form of a door hinge having a pair of interlock projectionsextending therefrom and arranged to have mating engagement in a pair ofinterlock recesses in one of said strips; said hinge being formed with arecess arranged to embrace the outer edge of the adjacent leg of saidU-shaped member.

16. A device, as set forth in claim 1, including a connecting memberconstituted by a relatively elongated bottom frame support; said bottomframe support comprising an angle member having interlock formations inone leg engageable with an interlock formation in one of said strips,and having a second leg extending at right angles to said first leg;said second leg having an aperture therethrough for fastening means tosecure said bottom frame support to a bottom frame or panel.

1. In a device for assembling wooden furniture panels to form a piece offurniture, and of the type including elongated U-shaped members arrangedto conformingly seat edges of panels and having interlock formationsinterengageable with mating interlock formations on connecting memberssecurable to other panels, the improvement comprising, in combination,an elongated U-shaped member of substantially rectangular crosssectionincluding a web and a pair of legs extending perpendicularly from saidweb to define a groove; a pair of substantially similar elongatedsubstantially rectangular strips each positioned against the innersurface of a respective leg and having an inner edge seating on saidweb, the outer edges of said strips being formed with said interlockformations; a first wooden furniture paneL seated in said groove; thethickness of said strips relative to the interior width of said U-shapedmember being such that the lateral spacing between said strips issubstantially equal to the thickness of said first wooden furniturepanel, so that said first panel is tightly engaged between said strips;means restraining displacement of said strips outwardly of said groove;at least one metal connecting member having interlock formationsmatingly engaged in interlock formations of one of said strips, eachconnecting member extending outwardly from said groove; and a woodenfurniture panel secured to each connecting member.
 2. A device, as setforth in claim 1, wherein said strip formations have a T-shapedconfiguration in the plane extending along the surface of said leg ofsaid U-shaped member.
 3. A device, as set forth in claim 2, wherein theinterlock formations on said connecting means have a T-shapedconfiguration similar to the T-shaped configuration of the interlockformations of said strips.
 4. A device, as set forth in claim 1, whereinstops extend along each of the outer edges of said legs substantiallyperpendicularly to the legs and partly across the opening to the groovein said U-shaped member, said stops being arranged in engagement withthe outer edges of said strips.
 5. A device, as set forth in claim 1,wherein said legs of said U-shaped member and said strips have alignedbores therethrough, a cross connector arranged to be fitted into a borein the panel to be secured within said groove of said U-shaped memberand to be aligned with the bores in said legs and strips, and securingmeans arranged to extend through the bores in said legs and strips intosaid cross connector for securing the panel within said groove and forsecuring said legs and strips together.
 6. A device, as set forth inclaim 5, wherein said cross connector has a polygonally shapedtransverse cross section for preventing turning when it is positionedwithin a panel, said cross connector having a bore therethrough alignedwith the bores in said legs and strips, said cross connector having alength substantially equal to the thickness of the panel positionedwithin said groove, and said securing means comprising threaded memberseach arranged to pass through the bores in one said leg and strip and tobe secured within the bore in said cross connector for securing theU-shaped member and the panel positioned within its groove together. 7.A device, as set forth in claim 1, wherein a flange extends along andoutwardly from the outer surface of at least one of said legs, saidflange being positioned intermediate said web and the outer edge of saidleg.
 8. A device, as set forth in claim 7, wherein the distance of saidflange from the outer edge of said leg corresponds substantially to thethickness of a panel to be secured against said flange on the sidethereof facing toward the outer edge of said leg.
 9. A device, as setforth in claim 7, wherein the distance of said flange from the outerwall of said web of said U-shaped member corresponds substantially tothe wall thickness of a panel to be positioned between the flange andthe outer surface of said web.
 10. A device, as set forth in claim 7,including a connecting member in the form of an abutment plate arrangedto be interlocked with one of said strips; said abutment platecomprising a plate part and a pair of T-shaped projections extendingperpendicularly from said plate part and constituting said interlockformations, said T-shaped projections having mating engagement inT-shaped recesses in the associated strip.
 11. A device, as set forth inclaim 10, wherein said plate part of said abutment plate has an openingtherethrough, an elastically deformable button-like member positionedwithin said opening and arranged to extend from one surface of saidplate part into engagement with the panel to be secured thereby andproviding contacting engagement with the panel on one sIde while theopposite side of the panel is secured against said flange extendingoutwardly from said leg on said U-shaped member.
 12. A device, as setforth in claim 4, wherein the surfaces of said stops adjacent theopening into said groove in said U-shaped member are chamfered.
 13. Adevice, as set forth in claim 4, wherein said strips have a thicknesswhich corresponds to the dimension of said stops extending from theinner surface of said legs of said U-shaped member.
 14. A device, as setforth in claim 4, wherein said strips have a thickness which is greaterthan the dimension of said stops extending from the inner surface ofsaid legs of said U-shaped member so that the strips extend further intosaid groove in said U-shaped member than do said stops.
 15. A device, asset forth in claim 1, including a connecting member in the form of adoor hinge having a pair of interlock projections extending therefromand arranged to have mating engagement in a pair of interlock recessesin one of said strips; said hinge being formed with a recess arranged toembrace the outer edge of the adjacent leg of said U-shaped member. 16.A device, as set forth in claim 1, including a connecting memberconstituted by a relatively elongated bottom frame support; said bottomframe support comprising an angle member having interlock formations inone leg engageable with an interlock formation in one of said strips,and having a second leg extending at right angles to said first leg;said second leg having an aperture therethrough for fastening means tosecure said bottom frame support to a bottom frame or panel.